摘要：
The highest building in our city has only one elevator. A request list is made up with N positive numbers. The numbers denote at which floors the elev 阅读全文
摘要：
Given a sequence of K integers { N~1~, N~2~, ..., N~K~ }. A continuous subsequence is defined to be { N~i~, N~i+1~, ..., N~j~ } where 1 <= i <= j <= K 阅读全文